From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0AEC1C77B7F for ; Fri, 19 May 2023 10:40:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231488AbjESKkb (ORCPT ); Fri, 19 May 2023 06:40:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231496AbjESKkY (ORCPT ); Fri, 19 May 2023 06:40:24 -0400 Received: from mail-wm1-x32d.google.com (mail-wm1-x32d.google.com [IPv6:2a00:1450:4864:20::32d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DA0E19A9 for ; Fri, 19 May 2023 03:40:02 -0700 (PDT) Received: by mail-wm1-x32d.google.com with SMTP id 5b1f17b1804b1-3f41dceb9d1so29753955e9.1 for ; Fri, 19 May 2023 03:40:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1684492800; x=1687084800; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=hElkZpZGFxCq2hRA3HiBp8TkWcTF4I4dj9+bw52Lj/8=; b=Z45E2XWnOWUEsXEdE8TOvsyDTHVft/cWpy48WHE/+3mX/c7wvnA71FMvwFI+nlKnou YDM12u+urpiG5bfv6c8ib5vy79jW3vqJpz/B0e6/PQRtWTrcXuDNiM/FDHWYnzBjXliB /ALU5Xz8IbnNGeV10NY+qKD7G+7mI0j0uRh14Ga8oW/cLgLXAYqPyKVHc0ZE/P3TIymt s6Z/RlIBsbjjAcGajhjDhHjYQ7vXhuEj736RyTudCTRq/y/+2kSuZupEGZGxWuAI/J9z fOejTxLU13sw3d9ZqTqk72NLVPRjf3ss7Dx695UgjvvXADhDRh+qeVbapljCIG7w6BFw 2mhw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684492800; x=1687084800; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=hElkZpZGFxCq2hRA3HiBp8TkWcTF4I4dj9+bw52Lj/8=; b=he7ZbtFsrb5F0EArGTNT2nsTW3/qKS4P47/bvAEXsyQ3Q1vo+LPMBxvzXgnmMQjqSj gFkLsK4gGVXtaLPdwu+p5iji4B2AlkpsjZ2mF/sGvXrbZsHgjody9/CyE0Y7ydWjFWXz D60MKXjCr8jjVpSflHFBs4QLc1S6+DWPhHjnS+uPX/YPdRQpayAxIKZ7v/atewXSMpls wtc0aZF85QzBZQXk0HFigqtosIHRFnuQHRc89c9HdQFX4MFb1RgwkJ7IHqTe5iyTg825 sGB0ZiKHccH1zNoWCe1AeU6POFz12caJFbgeZSvbnykaIaBMDnGd1TwM0KvQFDqeP9GV YW2Q== X-Gm-Message-State: AC+VfDy4oEH+ajWId4QEqUIKiYTgJ6Bu1JoKixs3vJXs6pquZE8iWS7q W6uWkfaZuxHfV1E5WWbk2JjUKg== X-Google-Smtp-Source: ACHHUZ4w1xxWTdD9aPa8s/wTf1iTxD/jsKsKiv3au9oS9eSFzuqxNS8NL35Ec2ej7sqUrxOEh9N/JA== X-Received: by 2002:a7b:cb90:0:b0:3f3:1cb7:b2a6 with SMTP id m16-20020a7bcb90000000b003f31cb7b2a6mr1002586wmi.6.1684492800642; Fri, 19 May 2023 03:40:00 -0700 (PDT) Received: from [192.168.1.195] ([5.133.47.210]) by smtp.googlemail.com with ESMTPSA id g21-20020a7bc4d5000000b003f42456c490sm1960510wmk.33.2023.05.19.03.39.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 19 May 2023 03:39:59 -0700 (PDT) Message-ID: <4aa42c38-e0e2-4d2d-bfe2-15bc151f7117@linaro.org> Date: Fri, 19 May 2023 11:39:59 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Subject: Re: [PATCH] misc: fastrpc: Fix double free of 'buf' in error path Content-Language: en-US To: Dan Carpenter Cc: Sukrut Bellary , Abel Vesa , Amol Maheshwari , Arnd Bergmann , Greg Kroah-Hartman , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org, Shuah Khan References: <20230518100829.515143-1-sukrut.bellary@linux.com> <9194ebdf-f335-4cd6-bf89-bb4f86a57784@kili.mountain> From: Srinivas Kandagatla In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 19/05/2023 11:22, Dan Carpenter wrote: >> ----------------------->cut<--------------------------- >> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c >> index f60bbf99485c..3fdd326e1ae8 100644 >> --- a/drivers/misc/fastrpc.c >> +++ b/drivers/misc/fastrpc.c >> @@ -1891,7 +1891,8 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl, >> char __user *argp) >> &args[0]); >> if (err) { >> dev_err(dev, "mmap error (len 0x%08llx)\n", buf->size); >> - goto err_invoke; >> + fastrpc_buf_free(buf); >> + return err; >> } >> >> /* update the buffer to be able to deallocate the memory on the DSP >> */ >> @@ -1930,11 +1931,7 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl, >> char __user *argp) >> return 0; >> >> err_assign: >> - fastrpc_req_munmap_impl(fl, buf); >> -err_invoke: >> - fastrpc_buf_free(buf); >> - >> - return err; >> + return fastrpc_req_munmap_impl(fl, buf); > > This will return success if copy_to_user() fails. > that is true, using return value of fastrpc_req_munmap_impl does not really make sense here we should just return err in either case to the user. --srini > regards, > dan carpenter >